Re: [Patch v4 00/18] NUMA aware page table allocation

From: Mingwei Zhang
Date: Tue Mar 07 2023 - 13:24:43 EST


On Mon, Mar 06, 2023, Vipin Sharma wrote:
> Hi,
>
> This series build up based on the feedback on v3.
>
> Biggest change in features is to enable NUMA aware page table per VM
> basis instead of using a module parameter for all VMs on a host. This
> was decided based on an internal discussion to avoid forcing all VMs to
> be NUMA aware on a host. We need to collect more data to see how much
> performance degradation a VM can get in negative testing, where vCPUs in
> VM are always accessing remote NUMA nodes memory instead of staying
> local compared to a VM which is not NUMA aware.
>
> There are other changes which are mentioned in the change log below for
> v4.
>
> Thanks
> Vipin
>
> v4:
> - Removed module parameter for enabling NUMA aware page table.

Could you have a space before the dash? I think the mutt mistakenly
treats it as a 'diff' where you removes a line.
> - Added new capability KVM_CAP_NUMA_AWARE_PAGE_TABLE to enable this
> feature per VM.
> - Added documentation for the new capability.
> - Holding mutex just before the top up and releasing it after the
> fault/split is addressed. Previous version were using spinlocks two
> times, first time for topup and second time fetching the page from
> cache.
> - Using the existing slots_lock for split_shadow_page_cache operations.
> - KVM MMU shrinker will also shrink mm_shadow_info_cache besides
> split_shadow_page_cache and mmu_shadow_page_cache.
> - Reduced cache default size to 4.
> - Split patches into smaller ones.
>
> v3: https://lore.kernel.org/lkml/20221222023457.1764-1-vipinsh@xxxxxxxxxx/
> - Split patches into smaller ones.
> - Repurposed KVM MMU shrinker to free cache pages instead of oldest page table
> pages
> - Reduced cache size from 40 to 5
> - Removed __weak function and initializing node value in all architectures.
> - Some name changes.
>
> v2: https://lore.kernel.org/lkml/20221201195718.1409782-1-vipinsh@xxxxxxxxxx/
> - All page table pages will be allocated on underlying physical page's
> NUMA node.
> - Introduced module parameter, numa_aware_pagetable, to disable this
> feature.
> - Using kvm_pfn_to_refcounted_page to get page from a pfn.
>
> v1: https://lore.kernel.org/all/20220801151928.270380-1-vipinsh@xxxxxxxxxx/
>
> Vipin Sharma (18):
> KVM: x86/mmu: Change KVM mmu shrinker to no-op
> KVM: x86/mmu: Remove zapped_obsolete_pages from struct kvm_arch{}
> KVM: x86/mmu: Track count of pages in KVM MMU page caches globally
> KVM: x86/mmu: Shrink shadow page caches via MMU shrinker
> KVM: x86/mmu: Add split_shadow_page_cache pages to global count of MMU
> cache pages
> KVM: x86/mmu: Shrink split_shadow_page_cache via MMU shrinker
> KVM: x86/mmu: Unconditionally count allocations from MMU page caches
> KVM: x86/mmu: Track unused mmu_shadowed_info_cache pages count via
> global counter
> KVM: x86/mmu: Shrink mmu_shadowed_info_cache via MMU shrinker
> KVM: x86/mmu: Add per VM NUMA aware page table capability
> KVM: x86/mmu: Add documentation of NUMA aware page table capability
> KVM: x86/mmu: Allocate NUMA aware page tables on TDP huge page splits
> KVM: mmu: Add common initialization logic for struct
> kvm_mmu_memory_cache{}
> KVM: mmu: Initialize kvm_mmu_memory_cache.gfp_zero to __GFP_ZERO by
> default
> KVM: mmu: Add NUMA node support in struct kvm_mmu_memory_cache{}
> KVM: x86/mmu: Allocate numa aware page tables during page fault
> KVM: x86/mmu: Allocate shadow mmu page table on huge page split on the
> same NUMA node
> KVM: x86/mmu: Reduce default mmu memory cache size
>
> Documentation/virt/kvm/api.rst | 29 +++
> arch/arm64/kvm/arm.c | 2 +-
> arch/arm64/kvm/mmu.c | 2 +-
> arch/mips/kvm/mips.c | 3 +
> arch/riscv/kvm/mmu.c | 8 +-
> arch/riscv/kvm/vcpu.c | 2 +-
> arch/x86/include/asm/kvm_host.h | 17 +-
> arch/x86/include/asm/kvm_types.h | 6 +-
> arch/x86/kvm/mmu/mmu.c | 319 +++++++++++++++++++------------
> arch/x86/kvm/mmu/mmu_internal.h | 38 ++++
> arch/x86/kvm/mmu/paging_tmpl.h | 29 +--
> arch/x86/kvm/mmu/tdp_mmu.c | 23 ++-
> arch/x86/kvm/x86.c | 18 +-
> include/linux/kvm_host.h | 2 +
> include/linux/kvm_types.h | 21 ++
> include/uapi/linux/kvm.h | 1 +
> virt/kvm/kvm_main.c | 24 ++-
> 17 files changed, 386 insertions(+), 158 deletions(-)
>
> --
> 2.40.0.rc0.216.gc4246ad0f0-goog
>

May I know your base? It seems I cannot apply the series to kvm/master
or kvm/queue without manual manipulation.